Syrphidae, an insect of Diptera. [1] Adults grow from small to large. The body is wide or slender, the body color is single and dark, or there are often bright stripes such as yellow, orange and gray, and some species have metallic colors such as blue, green and copper, which look like bees. Big head. Male eyes are one, female eyes are free, and both sexes are free. Generally speaking, the eggs of Scaeva pyrastri are white and long, and the eggshell has a net decorative pattern.